History
YoYo Wiki says the Twin Twirler was introduced in the early 1950s at the New York Toy Fair, after Kusan arranged with the patent holder of a combination yo-yo and spin top. The Yo-Yo Museum notes the inventor was Wallace F. Darden of Springfield, Tennessee, granted US patent 2,614,364 on October 21, 1952. It came in several body styles, sold as the Falcon (finned faces), Flying Eagle (pointed halves) and Bat models. The wiki says they were produced for only two years; the Museum dates the Falcon and Flying Eagle to 1952 and the Bat to 1953-1961, with later versions by Marketoy and Coleman. Kusan was among the first manufacturers to use plastic for yo-yos.
